Do hearing aids help maintain word recognition scores?

My wife has profound hearing loss: her right ear is -115 DB.

In the left ear otosclerosis has attacked the nerve and all she hears is noise at about 95 DB loss (I presume the loss is higher on the right here because the hearing aid is been blasting at levels way above what’s recommended for her to hear anything). Lately it seems like her discrimination has been worse;her last hearing test five years ago it was about 50%). She has to read my lips in conjunction with hearing and lately I’ve had to more and more enunciate words as carefully as possible. Also, she’s having more difficulty listening to music (which she does on the tele-coil setting, which for her is better): she hears the sharp tones of piano music reasonably well but symphonies and choral music are sounding more and more muddy. Up to now I have assumed it was the nerve in the right ear being attacked.

But her previous audiologist told her about 15 years ago that hearing aids get muddy with age; we were never sure if she was just trying to sell new ones. Her current aid is the Phonak Naida Q90, which she’s had for about 4 ½ years. Any thoughts on this? She’s probably due for a new aid anyway.(She has Cros for the left side.)